Physical Sciences and Mathematics Commons^™

Enzymatic Synthesis Of Magnetic Nanoparticles, Arati G. Kolhatkar, Chamath Dannongoda, Katerina Kourentzi, Andrew C. Jamison, Ivan Nekrashevich, Archana Kar, Eliedonna Cacao, Ulrich Strych, Irene Rusakova, Karen S. Martirosyan, Dmitri Litvinov, T. Randall Lee, Richard C. Willson

Physics and Astronomy Faculty Publications and Presentations

We report the first in vitro enzymatic synthesis of paramagnetic and antiferromagnetic nanoparticles toward magnetic ELISA reporting. With our procedure, alkaline phosphatase catalyzes the dephosphorylation of L-ascorbic-2-phosphate, which then serves as a reducing agent for salts of iron, gadolinium, and holmium, forming magnetic precipitates of Fe45±14Gd5±2O50±15 and Fe42±4Ho6±4O52±5. The nanoparticles were found to be paramagnetic at 300 K and antiferromagnetic under 25 K. Although weakly magnetic at 300 K, the room-temperature magnetization of the nanoparticles found here is considerably greater than that of analogous chemically-synthesized LnxFeyOz (Ln = Gd, Ho) samples reported previously. At 5 K, the nanoparticles showed a …